CZ:Featured article/Current: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Chunbum Park
(→‎Human rights: set theory)
imported>John Stephenson
(template)
 
(85 intermediate revisions by 5 users not shown)
Line 1: Line 1:
== '''[[Set theory]]''' ==
{{:{{FeaturedArticleTitle}}}}
----
<small>
A '''set''', in [[mathematics]], is a collection of distinct entities, called its elements, considered as a whole. The early study of sets led to a family of [[paradox]]es and apparent contradictions. It therefore became necessary to abandon "naïve" conceptions of sets, and a precise definition that avoids the paradoxes turns out to be a tricky matter. However, some unproblematic examples from naïve set theory will make the concept clearer. These examples will be used throughout this article:
==Footnotes==
 
* A = the set of the numbers 1, 2 and 3.
* B = the set of primary light colors -- red, green and blue.
* C = the empty set (the set with no elements).
* D = the set of all books in the British Library.
* E = the set of all positive integers, 1, 2, 3, 4, and so on.
 
Note that the last of these sets is infinite.
 
A set is the collection of its elements considered as a single, abstract entity. Note that this is different from the elements themselves, and may have different properties. For example, the elements of D are flammable (they are books), but D itself is not flammable, since [[abstract objects]] cannot be burnt.
''[[Set theory|.... (read more)]]''
 
{| class="wikitable collapsible collapsed" style="width: 90%; float: center; margin: 0.5em 1em 0.8em 0px;"
|-
! style="text-align: center;" | &nbsp;[[Set theory|notes]]
|-
|
{{reflist|2}}
{{reflist|2}}
|}
</small>

Latest revision as of 09:19, 11 September 2020

The Mathare Valley slum near Nairobi, Kenya, in 2009.

Poverty is deprivation based on lack of material resources. The concept is value-based and political. Hence its definition, causes and remedies (and the possibility of remedies) are highly contentious.[1] The word poverty may also be used figuratively to indicate a lack, instead of material goods or money, of any kind of quality, as in a poverty of imagination.

Definitions

Primary and secondary poverty

The use of the terms primary and secondary poverty dates back to Seebohm Rowntree, who conducted the second British survey to calculate the extent of poverty. This was carried out in York and was published in 1899. He defined primary poverty as having insufficient income to “obtain the minimum necessaries for the maintenance of merely physical efficiency”. In secondary poverty, the income “would be sufficient for the maintenance of merely physical efficiency were it not that some portion of it is absorbed by some other expenditure.” Even with these rigorous criteria he found that 9.9% of the population was in primary poverty and a further 17.9% in secondary.[2]

Absolute and comparative poverty

More recent definitions tend to use the terms absolute and comparative poverty. Absolute is in line with Rowntree's primary poverty, but comparative poverty is usually expressed in terms of ability to play a part in the society in which a person lives. Comparative poverty will thus vary from one country to another.[3] The difficulty of definition is illustrated by the fact that a recession can actually reduce "poverty".

Causes of poverty

The causes of poverty most often considered are:

  • Character defects
  • An established “culture of poverty”, with low expectations handed down from one generation to another
  • Unemployment
  • Irregular employment, and/or low pay
  • Position in the life cycle (see below) and household size
  • Disability
  • Structural inequality, both within countries and between countries. (R H Tawney: “What thoughtful rich people call the problem of poverty, thoughtful poor people call with equal justice a problem of riches”)[4]

As noted above, most of these, or the extent to which they can be, or should be changed, are matters of heated controversy.

Footnotes

  1. Alcock, P. Understanding poverty. Macmillan. 1997. ch 1.
  2. Harris, B. The origins of the British welfare state. Palgrave Macmillan. 2004. Also, Oxford Dictionary of National Biography.
  3. Alcock, Pt II
  4. Alcock, Preface to 1st edition and pt III.